Allow artd to scan system_data_file:dir on Wembley. am: 98b7c7f259

Original change: https://android-review.googlesource.com/c/device/mediatek/wembley-sepolicy/+/2376031

Change-Id: I58228c2eace0ce0a70c84f47672739560b21f635
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>